package com.hmdp.service.impl;

import cn.hutool.core.lang.UUID;
import com.hmdp.dto.Result;
import com.hmdp.entity.SeckillVoucher;
import com.hmdp.entity.VoucherOrder;
import com.hmdp.mapper.VoucherOrderMapper;
import com.hmdp.service.ISeckillVoucherService;
import com.hmdp.service.IVoucherOrderService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.utils.RedisIdWork;
import com.hmdp.utils.SimpleRedisLock;
import com.hmdp.utils.UserHolder;
import org.aspectj.weaver.ast.Var;
import org.redisson.api.RLock;
import org.redisson.api.RedissonClient;
import org.springframework.aop.framework.AopContext;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import java.time.LocalDateTime;
import java.util.Collections;
import java.util.concurrent.Executor;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
public class VoucherOrderServiceImpl extends ServiceImpl<VoucherOrderMapper, VoucherOrder> implements IVoucherOrderService {

    @Resource
    private ISeckillVoucherService seckillVoucherService;

    @Resource
    private RedisIdWork redisIdWork;


    @Resource
    private StringRedisTemplate stringRedisTemplate;

    @Resource
    private RedissonClient redissonClient;

    private static final String ID_PREFIX= UUID.randomUUID().toString(true)+"-";

    private static final DefaultRedisScript<Long> SECKILL_SCRIPT;

    private  static  final ExecutorService SECKILL_ORDER_EXECUTOR= Executors.newSingleThreadExecutor();


    static {
        SECKILL_SCRIPT=new DefaultRedisScript<>();
        SECKILL_SCRIPT.setLocation(new ClassPathResource("seckill.lua"));
        SECKILL_SCRIPT.setResultType(Long.class);
    }


//    @PostConstruct
//    private void init(){
//        SECKILL_ORDER_EXECUTOR.submit();
//
//    }
//
//    private  class  VoucherOrderHandler implements  Runnable{
//
//
//        @Override
//        public void run(){
//
//            while (true)
//
//
//
//
//
//        }
//
//
//    }
//


//    @Override
//    public Result seckillVoucher(Long voucherId) {
//
//        //获取用户
//        Long userId = UserHolder.getUser().getId();
//
//        //获取订单id
//        long orderId= redisIdWork.nextId("order");
//
//        //执行脚本
//        Long result=stringRedisTemplate.execute(
//                SECKILL_SCRIPT,
//                Collections.emptyList(),
//                voucherId.toString(),
//                userId.toString(),
//                String.valueOf(orderId)
//        );
//
//        //判断结果是否为0
//        int r=result.intValue();
//        if(r!=0)
//        {
//            //不为0，没有购买资格
//            return Result.fail(r==1?"库存不足":"不能重复下单");
//
//        }
//
//
//
//
//    }
//



    @Override
    public Result seckillVoucher(Long voucherId) {

        //获取用户
        Long userId=UserHolder.getUser().getId();

        //执行lua脚本
        Long result =stringRedisTemplate.execute(
          SECKILL_SCRIPT,
                Collections.emptyList(),
                voucherId.toString(),
                userId.toString()
        );

        //判断结果是否为0
        int r=result.intValue();
        if(r!=0)
        {
            //不为0，没有购买资格
            return Result.fail(r==1?"库存不足":"不能重复下单");

        }
        //为零，有购买资格，把下单信息保存到阻塞队列中
        long orderId=redisIdWork.nextId("order");

        //为零有购买资格，把下单信息保存到阻塞队列
        VoucherOrder voucherOrder = new VoucherOrder();
        //订单id

        voucherOrder.setId(orderId);

        //用户id

        voucherOrder.setUserId(userId);

        //代金券id
        voucherOrder.setVoucherId(voucherId);


        //返回订单id


        return Result.ok(orderId);


    }


//    @Override
//    public Result seckillVoucher(Long voucherId) {
//
//        //1.查询优惠劵
//        SeckillVoucher voucher = seckillVoucherService.getById(voucherId);
//
//        //2.判断秒杀是否开始
//        if(voucher.getBeginTime().isAfter(LocalDateTime.now()))
//        {
//            return Result.fail("秒杀尚未开始！");
//        }
//
//        //3.判断秒杀是否已经结束
//        if(voucher.getEndTime().isBefore(LocalDateTime.now()))
//        {
//            return Result.fail("秒杀已结束！");
//        }
//
//        //4.判断库存实发充足
//        if(voucher.getStock()<1)
//        {
//            //库存不足
//            return Result.fail("库存不足！");
//        }
//        Long userId = UserHolder.getUser().getId();
//
//        //创建锁对象
////        SimpleRedisLock lock = new SimpleRedisLock("order:" + userId, stringRedisTemplate);
//        RLock lock = redissonClient.getLock("lock:order:" + userId);
//
//        //获取锁
//        boolean isLock = lock.tryLock();
//
//        //判断是否获取锁成功
//        if(!isLock)
//        {
//            //获取锁失败，返回错误或重试
//            return Result.fail("不允许重复下单！");
//        }
//
//
//        try {
//            IVoucherOrderService proxy = (IVoucherOrderService) AopContext.currentProxy();
//            return proxy.creatVoucherOrder(voucherId);
//        } finally {
//
//            //释放锁
//            lock.unlock();
//        }
//
//
//    }


//    @Transactional
    public  Result creatVoucherOrder(Long voucherId)
    {
        Long userId = UserHolder.getUser().getId();


            //一人一单
            //根据用户ID和订单ID查询是否用订单数大于0
            int count = query().eq("user_id", userId)
                    .eq("voucher_id", voucherId)
                    .count();

            if (count > 0) {
                return Result.fail("用户已购买过一次！");
            }


            //5.扣减库存
            boolean success = seckillVoucherService.update().setSql("stock=stock-1")
                    .eq("voucher_id", voucherId)
                    .gt("stock", 0)
                    .update();
            if (!success) {
                //扣减失败
                return Result.fail("库存不足！");
            }

            //6.创建订单
            VoucherOrder voucherOrder = new VoucherOrder();
            //订单id
            Long orderId = redisIdWork.nextId("order");
            voucherOrder.setId(orderId);

            //用户id

            voucherOrder.setUserId(userId);

            //代金券id
            voucherOrder.setVoucherId(voucherId);

            //将定单写入数据库
            save(voucherOrder);

            //7.返回订单id

            return Result.ok(orderId);
        }










}
